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<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>EL的基本语法</title>
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<h2>常量</h2>
${"dsa" }<br>
${1 }<br>
${true }<br>
${'形象' }<br>
<h3>jsp域对象里的key</h3>
<%
//在page域里保存元素
pageContext.setAttribute("key01", "value01");
pageContext.setAttribute("key02", "value02", pageContext.REQUEST_SCOPE);
pageContext.setAttribute("key03", "value03", pageContext.SESSION_SCOPE);
pageContext.setAttribute("key04", "value04", pageContext.APPLICATION_SCOPE);

%>
<!-- pageContext.findAttribute(name) -->
${key01 }<br>
${key02 }<br>
${key03 }<br>
${key04 }<br>
${key05 }<br>
<%
Object content=pageContext.findAttribute("key05");
if(content==null){
	out.write("null");
}
%>
<h2>特殊语法</h2>
${'${}' }<br>
</body>
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